Prior attempts to utilize pressure sensitive technology to adhesively mount face pieces for pick-off have generally resulted in a "wet" or sticky surface being exposed upon pick-off. Varying release characteristics have also been a problem where silicone-based release coatings have been applied to porous face materials, due to the difficulty of achieving uniformity of the silicone-based coatings. Also it is difficult to print on silicone-based coatings, so that printing of the underside of the face piece cannot be satisfactorily accomplished.
One prior art proposal for solution of the foregoing problems is found in Eagon U.S. Pat. No. 4,398,985 which provides "dry" pick-off and avoids reliance on a silicone-based coating for the pick-off release. However, such prior art proposal relies on relatively costly polymer coating steps, and requires custom label manufacture in association with the packaging or labelling operation. Such prior art proposall does not lend itself to established procedures in the packaging industry whereby pressure-sensitive adhesive labels are commonly applied to packages after being converted from label face stock and pressure sensitive stock into a series of temporarily supported labels by laminating, die cutting and then stripping the resulting matrix of waste material. These procedures are widely accepted and the conversion equipment to practice them is already widely possessed and used by "converters" or label manufacturers. In these procedures, the liner-supported labels produced by such a converter can be printed or decorated, in closely controlled proper registration with the die cuts, and can then be used by packagers (customers of the converters) on high speed automatic labelling machines to dispense and apply individual labels to individual packages, in a manner widely practiced in the industry.
As to the "renewable surface" aspect of the invention, it is known to coextrude a plurality of films which are combined into multilayer casings and the like. However, it is not believed that anyone has previously thought of exploiting the peelability potential of coextruded films to provide renewable surfaces for manufactured products such as paint pans or medical trays, let alone conceiving how to make such exploitation feasible for manufacturers of such products, who lack expertise and equipment necessary for coextruding films and for applying coextruded films to their products.